High frequency circuit element and high frequency circuit module

Abstract

A high-frequency circuit device includes a dielectric member 1, a shielding conductor 2 surrounding the dielectric member 1, a support member 3 for fixing and supporting the dielectric member 1, and a pair of transmission lines 4 each of which is formed of a microstrip-line. Each of the transmission lines includes a substrate 6 formed of a dielectric material, a strip conductor 5, and an earth conductor layer 9. An end portion of the strip conductor 5 faces part of the dielectric member 1 and functions as a coupling probe for input / output coupling. Each of the transmission lines 4 is formed of a strip line, a mictostrip line, a coplanar line or the like, and has low-loss when connected to a circuit board.

Description

[0001] The present invention relates to high-frequency circuit devices and modules for resonance used in radio-communication systems or other devices dealing with high-frequency signals.[0002] Conventionally, high-frequency filters and other high-frequency circuit devices including a resonant body as a basic element are essential for communication systems. With a resonant body, among resonator bodies, using a dielectric material such as a high dielectric constant, low-loss ceramic material, a high-frequency circuit device functioning as a small and low-loss (high-Q) resonator can be achieved.[0003] Such a resonator can be disposed with other circuit elements such as an amplifier, an oscillator, and a mixer circuit on a substrate to make a high-frequency circuit have a module configuration. In this case, a high-frequency signal needs to be input / output to / from the resonator via a transmission line such as a stripline on the substrate. As an example of such high-frequency circuits usi...

AI Technical Summary

Benefits of technology

[0010] It is therefore an object of the present invention to provide low-loss, high-frequency circuit device and module in which a dielectric member is incorporated.

Problems solved by technology

First, since the dielectric member is used without being shielded, high-frequency signals (electromagnetic waves) from the dielectric member are emitted. The signal emission may cause an increase in the loss of a resonator, i.e., a reduction in the Q value of the resonator. Moreover, by the emitted electromagnetic waves, the dielectric member may be coupled with other circuits disposed on a substrate to make circuit operation unstable. Furthermore, in order to suppress the coupling between the dielectric member and other circuits by the emitted electromagnetic waves, it is necessary to dispose the dielectric member so as to be spaced apart from the other circuits by a certain distance. This is an obstacle to reduce the size of an entire module.

The above-described problems are more clearly noticed, as the frequency of high-frequency signals dealt with in a high-frequency circuit device is increased.

Therefore, they may be fatal problems in a millimeter wave band or the like.

Therefore, it may be difficult to obtain a desired coupling of the dielectric member with a stripline or the like disposed on the substrate.

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